Operation instructions for nitriding furnace
In the nitriding furnace, the nitriding process is carried out by first placing the stainless steel workpiece that has been normalized or quenched and tempered into a vacuum sealed tank, then introducing ammonia gas and heating the furnace temperature to 520 ℃ for a period of time. The duration of time varies depending on the material of the workpiece and the required thickness of the infiltration layer, ranging from 3 to 90 hours. The purpose is to form a nitrogen-containing strengthening layer on the surface of the workpiece, enhancing its hardness, wear resistance, fatigue limit, and excellent wear resistance.
The operation steps are as follows:
1.Before nitriding, it is essential to ensure that the surface of the mold is clean, free from rust, oil stains, and impurities.
- Thoroughly clean the workpiece with gasoline and alcohol to ensure a clean surface.
- Place the workpiece into the furnace and ensure that the furnace cover is evenly tightened with clamping bolts.
- The inlet of the furnace tank and furnace cover is connected to the cooling water circulation system, with the inlet at the bottom and the outlet at the top. At the same time, the furnace tank and furnace cover have independent inlet and outlet, and the water pipe connection follows the principle of low inlet and high outlet.
5.Before heating up, it is necessary to exhaust nitrogen gas first, and the exhaust flow rate should be greater than the actual usage. After exhausting for 10 minutes, set the temperature to 150 ℃, turn on automatic heating, and heat while exhausting for 2 hours. Then adjust the temperature to 530 ℃, reduce the ammonia flow rate, maintain positive pressure inside the furnace, and there is a weak upward pressure of gas flow at the exhaust port.
- When the furnace temperature reaches 530 ℃, constant temperature and current nitriding can begin for up to 3 to 20 hours, and then gradually increase the ammonia pressure for nitriding, lasting for 4 to 70 hours. After nitriding is completed, gradually reduce the ammonia pressure and carry out denitrification for approximately 1 to 2 hours. Finally, turn off the power and stop heating, but still maintain a small amount of ammonia to maintain positive pressure inside the furnace. Wait until the furnace temperature drops below 150 ℃ before stopping the ammonia supply and removing the workpiece.
Through the above steps, the nitriding process can be accurately executed in the nitriding furnace to achieve the expected surface treatment effect.